Results of the linear non-adiabatic (LNA) analysis with MESA-RSP. Positive and negative growth rates, γ for the fundamental mode are indicated in red and grey points, respectively. The black crosses are the selected models for non-linear analysis as summarized in Table 2. The vertical blue strip corresponds to the expected value of the mean effective temperature for Y Oph, i.e., T_eff = 5800 ± 100 K (Luck 2018; Proxauf et al. 2018; da Silva et al. 2022). The fundamental blue edge from Anderson et al. (2016) is shown for comparison (see their Fig. 2: Z = 0.14, ω_ini = 0.5, mix between 2nd and 3rd crossing) with ΔL ± 500 L_⊙.